Depression is a common and persistent problem after coronary artery bypass graft (CABG) surgery that complicates recovery, increases the risk of cardiac events, and may exacerbate the neurocognitive deficits that are often observed in post-CABG patients. Although CABG is one of the most frequently performed operations in the United States, there have not been any randomized, controlled trials of treatments for depression in this population. The aims of this study are (1) to compare the efficacy of cognitive behavior therapy (CBT), stress management (SM), and usual care (UC) for major depression following CABG surgery; (2) to determine the effects of CBT on neurocognitive performance, psychosocial adjustment, functional status, employment status, and health-related quality of life; and (3) to collect pilot data on the relationship between the treatment of depression and the 12-month incidence of cardiac and cerebrovascular events following CABG. Consenting patients will be screened for depression 4 to 6 weeks after surgery. Those who screen positive will return for a psycho-diagnostic evaluation and additional testing approximately 1 week later. A sample of 165 patients with major depression who meet all other eligibility criteria will be randomized to 12 weeks of CBT, SM, or UC with no restriction on non-study antidepressants. Participants in all 3 arms will be monitored for worsening depression and will be referred for additional care if needed. Depression outcomes will be assessed 12 weeks post-randomization and 6 months after surgery (2 months after termination of CBT or SM.) The primary hypothesis is that the post-treatment severity of depression is lower in patients treated with CBT than with SM or UC, with baseline depression severity and non-study treatment as planned covariates. Secondary analyses will test the effects of treatment on remission, neurocognitive and functional recovery, quality of life, and examine the relationships between treatment process and outcome variables.